Get 1769 i/o module status – Rockwell Automation 1769-ADN Compact I/O 1769-ADN DeviceNet Adapter User Manual

Page 162

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Publication 1769-UM001B-EN-P - October 2002

B-4 Explicit Messaging Application Examples

Get 1769 I/O Module Status

Use a “CIP Generic” MSG instruction to send the Get 1769 I/O Module
Status explicit message from a Logix5550 controller via a 1756-DNB
scanner on DeviceNet. You’ll see in the ladder logic example to
follow, a CIP Generic message is sent to the 1756-DNB scanner and
ultimately to the 1769-ADN and the 1769 I/O module in slot 10.

Use a “Single Parameter Read” MSG instruction for the Get 1769 I/O
Module Status message, where one word of status information is read
from the 1769 I/O module in slot 10. The user program consists of a
single rung containing a MSG instruction to accomplish the Get 1769
I/O Module Status.

The following correlates the CIP Generic message terminology with
DeviceNet command terminology and illustrates the values needed
specifically for the Get 1769 I/O Module Status message:

Values (Hexadecimal)

DeviceNet Terminology

CIP Generic Terminology

e

Service

1

Service Code

30c

Class

2

Object Type

10 (decimal)

Instance

3

Object ID

c

Attribute

4

Object Attribute

1

Service specifies the type of request being delivered. “e” hexadecimal is a “Single Parameter Read”.

2

Class specifies the desired DeviceNet class. “30c” hexadecimal is the class code for the object representing

1769 I/O.

3

Instance represents the slot number of the I/O module from which we want status information. “10” decimal

in this example is the analog output module in slot 10.

4

Attribute identifies the specific characteristics of the object towards which the transaction is directed.

“c” hexadecimal means Module Status.

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